Organic white pigment

ABSTRACT

A novel organic white pigment which can be applied to an organic white pigment composition useful as a paper coating agent or an aqueous or oily ink or paint is provided. This organic white pigment consists of an alkylene-bismelamine derivative, represented by the following general formula (I), ##STR1## wherein R is a hydrogen atom or a lower alkyl group containing 1 to 4 carbon atoms or alicyclic group, R 1 , R 2 , R 3 , and R 4  are respectively same or different hydrogen atoms or lower alkyl groups containing 1 to 4 carbon atoms, R 1 , and R 2 , or R 3 , and R 4  may respectively form heterocyclic groups with nitrogen atoms and X is a lower alkylene group containing 2 to 3 carbon atoms.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a novel organic white pigment which can beapplied to an organic white pigment composition useful as a papercoating agent or an aqueous or oily ink or paint.

2. Description of the Prior Art

Up to the present time, clay, kaolin clay, talc, calcium carbonate, zincoxide or titanium oxide have predominantly been used, individually or incombination, as a pigment component of a white pigment.

However, when this pigment component is used for the preparation of adispersed composition, the pigment component tends to be precipitatedbecause of being an inorganic material having a large density and it usdifficult to obtain a uniform and stable dispersed composition thereof.This is not preferable in view of the storage stability of thepigment-dispersed composition. Coating a sheet of paper with such apigment composition, for example, naturally results in increase of theweight of the paper. In addition, such an inorganic pigment has adisadvantage that compatibility with a reagent required for thepreparation of binders and other dispersed compositions is inferior.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a new organic whitepigment, whereby the disadvantages of the prior art can be overcome.

It is another object of the present invention to provide an organicwhite pigment excellent in compatibility with surfactants, organic colorpigments and other additives.

It is a further object of the present invention to provide organicpigment composition with excellent dispersion stability and storagestability.

These objects can be attained by an alkylenebismelamine derivative foran organic white pigment, represented by the following general formula(I), ##STR2## wherein R is a hydrogen atom or a lower alkyl groupcontaining 1 to 4 carbon atoms or alicyclic group, R₁, R₂, R₃ and R₄ arerespectively same or different hydrogen atoms or lower alkyl groupscontaining 1 to 4 carbon atoms, R₁, and R₂, or R₃ and R₄ mayrespectively form heterocyclic groups with nitrogen atoms and X is alower alkylene group containing 2 to 3 carbon atoms.

DETAILED DESCRIPTION OF THE INVENTION

The inventors have made various studies to solve the problems ofinorganic white pigments of the prior art, as described above, andconsequently, have found that an alkylenebismelamine derivative has veryexcellent properties as an organic white pigment. The present inventionis based on this finding.

Accordingly, the present invention provides an alkylenebismelaminederivative for an organic white pigment, represented by the foregoingGeneral Formula (I).

The alkylenebismelamine derivative of the present invention will now beillustrated in detail. In General Formula (I), R represents a hydrogenatom or lower alkyl group containing 1 to 4 carbon atoms such as methyl,ethyl, propyl or butyl group, or an alicyclic group such as cyclohexylgroup. R₁, R₂, R₃ and R₄ represent respectively same or differenthydrogen atoms and lower alkyl groups containing 1 to 4 carbon atomssuch as methyl, ethyl, propyl and butyl group. R₁ and R₂, or R₃ and R₄may respectively form heterocyclic groups with nitrogen atoms, forexample, piperidyl, morpholino groups, etc., and X represents a loweralkylene group containing 2 to 3 carbon atoms, for example, --CH₂ CH₂--or --CH₂ CH₂ CH₂ --.

The alkylenebismelamine derivative of the present invention, representedby General Formula (I), is a white crystal generally having a highmelting point (at least 300° C.) and thus exhibits an excellent heatresistance. Furthermore, this derivative has a high degree of whiteness,good hiding property and small specific gravity because of being anorganic compound, and further has a number of properties essential as apigment component, i.e. less solubility in various solvents and goodsolvent resistance.

The pigment component of the present invention, i.e. loweralkylenebismelamine derivative represented by General Formula (I), canreadily be prepared by the following process:

This process comprises reacting one equivalent of a cyanuric halide withfour equivalents of ammonia, a lower monoalkylamine or lowerdialkylamine, then reacting the resulting 2,4-diamino(di-lowermonoalkylamino or di-lower dialkyl-amino)-6-halogeno-1,3,5-triazine with1/2 equivalent of an alkylenediamine or substituted alkylenediamine.

Specifically, one equivalent of a cyanuric halide is dispersed in icewater with a small amount of a surfactant and maintained at 0° to 5° C.while stirring, to which an aqueous solution containing four equivalentsof ammonia (alternatively, lower mono- or dialkylamine) is dropwiseadded. After the dropwise addition, the mixture is heated to 40° to 45°C. and reacted for about 3 hours and the thus precipitated whitecrystals are then filtered. The resulting cake of 2,4-diamino (ordi-lower mono- or dialkylamino)-6-halogeno-1,3,5-triazine is dispersedin water, mixed with 1/2 equivalent of an alkylenediamine (orsubstituted alkylenediamine) and reacted at a temperature of 95° to 100°C. with agitation until the alkalinity disappears. While maintaining thesame temperature, an aqueous solution containing two equivalents ofsodium hydroxide is dropwise added thereto for about 2 hours. pH of thereaction mixture becomes about 8 and the content once becomes atransparent solution, after which white crystals are shortlyprecipitated. The reaction mixture is further maintained at 95° to 100°C. for about 3 hours to complete the reaction and then allowed to cool.When the temperature becomes about 50° C., the pH of the reactionmixture is adjusted to a weak alkalinity of about pH 10 and theprecipitated crystals are filtered, adequately washed with water anddried.

As the cyanuric halide, there is specifically used cyanuric chloride.Examples of the amine to be reacted with the cyanuric halide includeammonia, mono-(or di-)methylamine, mono-(or di-)ethylamine,dipropylamine, dibutylamine, morpholine, piperidine, etc. As thealkylenediamine, there can preferably be used ethylenediamine,N,N'-dimethylethylenediamine, N,N'-dicyclohexylethylene-diamine,propylenediamine and the like.

For the preparation of a pigment composition, the thus obtainedalkylenebismelamine derivative is used in known manner, i.e. in the formof a powder, aqueous dispersion, dispersion in a suitable organicsolvent or paste. As the organic solvent, there are generally usedalcohols, esters, ethers, halogen compounds, hydrocarbons, ketones andthe like. Specific examples thereof are butyl alcohol, ethyl acetate,Cellosolve, trichloroethylene, xylene, turpentine oil, solvent naphtha,methyl ethyl ketone, etc.

Preparation of the pigment composition in such a form can be carried outby dry or wet process using a known finely pulverizing machine such asball mill, sand mill, spead line mill, jet mill, etc. As occasiondemands, a method is employed comprising treating a pigment componentwith a surfactant and water using the above described pulverizingmachine to form an aqueous dispersion and then subjecting the dispersionto spray drying.

For the preparation of the dispersed composition in the above describedform, a suitable surfactant is generally used. Depending on the varietyof the form or the use of the composition, a suitable surfactant ismainly selected from anion type- or nonion type-surfactants. During orafter the preparation of the pigment composition, the commonly usedadditives for such a pigment composition, for example, gelationinhibitors, protective colloid agents, preservatives and, if necessary,fluorescent whitening agents can be added thereto depending on theobject of use or the form.

In addition, other organic color pigment components or pigmentcompositions can be added to the pigment component or pigmentcomposition of the present invention, thereby obtaining color pigmentcompositions with suitable color tones and concentrations. That is, thepigment component or composition according to the present invention isuseful as a base for other color pigment components or compositions.

The important feature of the white pigment composition using thealkylenebismelamine derivative of the present invention consists in thatthe pigment component has a small specific gravity because of being anorganic material and accordingly, the weight of a paper using the sameis lighter than that of a composition comprising an inorganic pigmentcomponent, resulting in lowering of the transporting or mailing cost.

Comparison of the specific gravity of an ethylenebismelaminecorresponding to General Formula (I) wherein all of R₁, R₂, R₃ and R₄are hydrogen atoms and X is --CH₂ CH₂ -- with that of a known inorganicpigment component is tabulated below:

                  TABLE 1                                                         ______________________________________                                        White Pigment Component                                                                            Specific Gravity                                         ______________________________________                                        Ethylenebismelamine  1.4                                                      Clay                 2.46˜2.63                                          Talc                 2.6˜2.8                                            Calcium Carbonate    2.83                                                     Titanium Oxide       3.7˜3.9                                            Zinc Oxide           5.4˜5.7                                            ______________________________________                                    

In this Table 1, the specific gravity of ethylenebismelamine is measuredby a measurement method using a specific gravity bottle, of the solidspecific gravity measurement methods according to JIS Z 8807.

The compound of General Formula (I) according to the present inventionis also excellent in whiteness degree and hiding power, in particular,when used as a white pigment. For example, the foregoingethylenebismelamine was used as a pigment component to prepare anaqueous dispersed composition (pigment component content=40 weight %,grain size=at most 5 μm ), while for comparison, calcium carbonate, clay(commercial name, HG-90) or calcined clay was used as a pigmentcomponent with the same concentration and composition to preparecomparative aqueous dispersed compositions. These aqueous dispersedcompositions were subjected to coating under the following conditions:

Wire Rod: No. 14

Coating Temperature: room temperature

Drying Condition: 120° C., 1 minute

and then dried to obtain black board-papers and Kinsha Paper -commercialnamemade by Kinshuseishi Co., Ltd. for comparison of the degree ofwhiteness, thus obtaining results as shown in Table 2. In Table 2, thelarger numerals show the more excellent whiteness degree.

                  TABLE 2                                                         ______________________________________                                                    Degree of Whiteness                                                           Black Board-Paper                                                                         Kinsha Paper                                          Pigment Composition                                                                         W(Lab)    WB      W(Lab) WB                                     ______________________________________                                        Ethylenebismelamine                                                                         85.91     76.02   92.30  84.45                                  Calcium Carbonate                                                                           55.70     32.22   91.22  81.62                                  Clay (HG-90)  63.49     47.72   91.25  80.97                                  Calcined Clay 81.39     71.78   91.55  81.63                                  Blank         22.84     4.93    89.46  78.31                                  ______________________________________                                    

Herein, W(Lab) is a Hunter whiteness degree of L, a, b system and WB isa whiteness degree obtained by a reflectivity of an optical fiber from asample, which are calculated by the following formulas 1 and 2:

    W(Lab)=100-{(100-L).sup.2 +a.sup.2 +b.sup.2 }.sup.1/2      Formula 1

    WB=Z×0.847                                           Formula 2

L, a, b are measures in the case of representing a color (whitenessdegree) on three-dimensional coordinates, measured by a color differencemeter, which is one of the commonly used color measurement methods. Thatis, when an ordinate and abscissa, vertically crossed on a same plane,are taken to define the crossed point as O and a vertical axis to theplane is taken from the crossed point O, a height from the plane isrepresented by L which means a lightness. a and b represent hues, arepresenting the hue in such a manner that the larger numeral shows alarger reddish degree in the right direction from the ordinate, i.e (+)side and a larger greenish degree in the left direction from theordinate, i.e. (-) side, and b representing the hue in such a mannerthat the (+) side from the abscissa shows a yellowish degree and the (-)side from the abscissa shows a bluish degree. When the colors (whitenessdegrees) of two samples are compared, therefore, the difference betweentheir distances from the standard point on the three-dimensionalcoordinates means "color difference" between the samples. In the case ofthe whiteness degree, L is the larger, a is the larger in the (+) sideand b is the larger in the (-) side, the whiteness is the larger.

z in Formula 2 (WB=Z×0.847) represents a reflectivity of an opticalfiber from a sample.

The numerals in Table 2 are average values of values obtained bymeasuring suitable sites on the coated papers using "Color MeasurementSystem Σ90" made by Nippon Denshoku Kogyo KK.

As is evident from Table 2, the whiteness degrees of the blackboardpaper and gold sand paper coated with the pigment composition of thepresent invention are more excellent with respect to both W(Lab) and WBthan when using the other three inorganic pigments. Thus, it is apparentthe pigment composition of the present invention gives also betterresults as to the hiding power.

EXAMPLES

The following examples are given in order to illustrate the presentinvention in detail without limiting the same, in which percents are tobe taken as those by weight unless otherwise indicated.

Synthetic Example 1 of Pigment Component

92.5 kg of cyanuric chloride is dispersed in about 500 kg of ice watercontaining 5 kg of a nonionic surfactant and maintained at at most 5° C.while stirring, to which about 134 kg of a 28% aqueous solution ofammonia was dropwise added for 2 to 3 hours. The mixture was then heatedto 40° to 45° C. for about 3 hours and maintained at about 70° C. forabout 30 minutes to complete the reaction. The reaction mixture was thenallowed to cool and the resulting crystals are filtered at about 40° C.to obtain a filter cake of 2,4- diamino-6-chloro-1,3,5-triazine. Theresulting filter cake was dispersed in water in an amount of about 10times as much as that of the cake, to which 15 kg of ethylenediamine wasadded, and the mixture was reacted at a temperature of 95° to 100° C.with agitation until the alkalinity gradually disappeared. Whilemaintaining the same temperature, an aqueous solution containing 40 kgof sodium hydroxide was dropwise added thereto for about 2 hours. pH ofthe reaction mixture became about 8 and the content was once dissolvedand became a transparent solution, after which white crystals wereshortly precipitated. The reaction mixture is further maintained at 95°to 100° C. for about 3 hours to complete the reaction and then allowedto cool. When the temperature became about 50° C., the pH of thereaction mixture was adjusted to a weak alkalinity of about pH 10 andthe precipitated crystals were filtered, adequately washed with waterand dried. The ethylenebismelamine obtained in this way was a whitepowder having MP of 314°-316° C., useful as a white pigment component.

Synthetic Examples 2 to 11 of Pigment Component

Synthetic Example 1 was repeated except using 56 kg ofN,N'-dicyclohexylethylenediamine instead of 15 kg of ethylenediamine,thus obtaining N,N'-dicyclohexylethylenebismelamine. This could berecrystallized from a mixed solvent of water and methycellosolve and wasa white crystal having MP of 338°-340° C., useful as a white pigmentcomponent, similar to the ethylenebismelamine.

Similarly, alkylenebismelamine derivatives as shown in Table 3 weresynthesized, which were also useful as a white pigment component.

                                      TABLE 3                                     __________________________________________________________________________    Substituent                                                                    ##STR3##                                                                           ##STR4##                                                                              ##STR5##                                                                              ##STR6##                                                                             ##STR7##                                                                               ##STR8##                                __________________________________________________________________________     1   NH.sub.2                                                                              NH.sub.2                                                                              H      CH.sub.2 CH.sub.2                                                                      314-316                                   2   NH.sub.2                                                                              NH.sub.2                                                                               ##STR9##                                                                            CH.sub.2 CH.sub.2                                                                      338-340                                   3   NHCH.sub.3                                                                            NHCH.sub.3                                                                            H      CH.sub.2 CH.sub.2                                                                      311-312                                   4   N(CH.sub.3).sub.2                                                                     N(CH.sub.3).sub.2                                                                     H      CH.sub.2 CH.sub.2                                                                      308-309                                   5   N(C.sub.2 H.sub.5).sub.2                                                              N(C.sub.2 H.sub.5).sub.2                                                              H      CH.sub.2 CH.sub.2                                                                      301-303                                   6   N(C.sub.4 H.sub.9).sub.2                                                              N(C.sub.4 H.sub.9).sub.2                                                              H      CH.sub.2 CH.sub.2                                                                      298-301                                   7                                                                                  ##STR10##                                                                             ##STR11##                                                                            H      CH.sub.2 CH.sub.2                                                                      >350                                      8                                                                                  ##STR12##                                                                             ##STR13##                                                                            H      CH.sub.2 CH.sub.2                                                                      >350                                      9   NH.sub.2                                                                              NH.sub.2                                                                              CH.sub.3                                                                             CH.sub.2 CH.sub.2                                                                      325-326                                  10   NH.sub.2                                                                              N(CH.sub.3).sub.2                                                                     H      CH.sub.2 CH.sub.2                                                                      311-313                                  11   NH.sub.2                                                                              NH.sub.2                                                                              H      CH.sub.2 CH.sub.2 CH.sub.2                                                             258-259                                  __________________________________________________________________________

Preparation Example of Ultra-fine Powder for White Pigment Composition

About 1 kg of the white powder obtained in Synthetic Example 1 wasultra-finely pulverized by means of a counter jet mill of fluidized bedtype (100 AFG Pulverizer --commercial name--made by Hosokawa Micron KK)for about 1 hour to obtain an ultra-fine powder with an average graindiameter of 1-2 μm.

The ultra-fine powders used in the following Examples were preparedaccording to the method of this Preparation Example.

Example 1

(Preparation of Aqueous Dispersion Composition)

59 kg of water was mixed with 1 kg of a nonionic dispersing agent and 40kg of the white pigment powder obtained in Synthetic Example 1 and thensubjected to a finely pulverizing treatment using a sand grinder of acontinuous and vertical type (made by Igarashi Kikai KK) to give a graindiameter of at most 1 μm and a mean grain diameter of 0.5 μm, thusobtaining an aqueous dispersion composition. This composition had a gooddispersion stability.

The aqueous dispersion composition used in the following Examples wasprepared according to the method of this Example 1.

Example 2

(Preparation of Oily Dispersion Composition)

45 kg of the white pigment powder obtained in Synthetic Example 2 and 15kg of a butyral dispersion resin were added to 40 kg of ethanol and themixture was subjected to a finely pulverizing treatment using a sandgrinder of a continuous and vertical type (made by Igarashi Kikai KK) togive a mean grain diameter of 0.3 to 0.4 μm, thus obtaining a dispersioncomposition in an alcohol medium.

The oily dispersion composition used in the following Examples wasprepared according to the method of this Example 2.

Example 3

(Coating Surface of Paper)

A coating color for a paper having a composition of the following Table4 was prepared.

                  TABLE 4                                                         ______________________________________                                        Anionic Dispersant                                                            Coating Color Composition for Paper:                                          ______________________________________                                        Ultra-fine Powder of White Pigment of                                                                   100      g                                          Synthetic Example 1                                                           Sodium Hexametaphopshate  0.3      g                                          Anionic Dispersant (Aron T-40 -commercial name-                                                         0.25     g                                          made by Toa Gosei Kagaku Kogyo KK)                                            Latex (JSR 0692)          12.5     g                                          25% Aqueous Ammonia Solution                                                                            1.3      g                                          Water                     80       g                                          total                     194.35   g                                          (Pigment Concentration    51.5%)                                              ______________________________________                                    

This coating color was caoted onto a commercially available fine qualitypaper to give a coverage of 22 g/cm² at room temperature using Wire RodNo. 14 (commercial name) and dried at 120° C. for 1 minute. Theresulting coated paper was more excellent in whiteness degree, lusterand smoothness as compared with a non-coated paper.

Example 4

(Printing)

A printing paste consisting of a composition of the following Table 5was prepared:

                  TABLE 5                                                         ______________________________________                                        Printing Paste Composition                                                    ______________________________________                                        Ultra-fine Powder of White Pigment of                                                                   20     g                                            Synthetic Example 1                                                           Acrylic Copolymer Binder  80     g                                            (NK Couper A-1 -commercial name-,                                             made by Shinnakamura Kagaku KK)                                               total                     100    g                                            ______________________________________                                    

The printing paste having the composition of Table 5 was printed andcoated on a cotton cloth in known manner, previously dried at 100° C.for 1-2 minutes and then subjected to a heat treatment at 145° C. for 3minutes. On the cotton cloth was obtained a clear and white printpattern, excellent in feeling as well as color fastness to washing.Similarly, clear and white printed products were obtained by printingpastes prepared using ultra-fine powders of white pigments of SyntheticExamples 2, 4 and 10.

Example 5

(Dope Dyeing of Polyesters)

1000 g of dimethyl terephthalate, 665 g of ethylene glycol, 0.55 g ofmanganese acetate and 0.18 g of antimony trioxide were charged in anautoclave of stainless steel, equipped with a cooler and stirrer, andheated. Release of methanol started at about 160° C. and continued forabout 2.5 hours. The temperature was 225° C. at the end of the reaction.5 g of the white pigment ultra-fine powder of Synthetic Example 1 and0.3 g of phosphoric acid were added to this melt and the pressure in theautoclave was lowered to 1 mmHg or lower, while maintaining thetemperature at 290° C., until reaching a desired degree ofpolymerization. The thus resulting polymer was spun by a known method ina nitrogen atmosphere at a pressure of 2 to 5 atm to obtain a polyesterfiber having a higher whiteness degree and more excellent color fastnessto washing and sunlight than white pigment free fibers.

Example 6

(Addition to Polyamide Resin)

1000 g of caprolactam, 30 g of water and 4 g of the ultra-fine powder ofSynthetic Example 7 were stirred at 240° C. under pressure for 4 hoursand heated for 60 minutes under opened state. The thus resultingpolyamide melt was extruded in a belt-like form through a nozzle of slittype, rapidly cooled in water, cut into chips and dried, thus obtainingopaque polyamide chips with good whiteness degree.

In the above described procedure, when using a suitable fluorescentwhitening agent, opaque polyamide chips with further high whitenessdegree were obtained.

Example 7

(Addition to Polvinyl Chloride Resin

1000 g of a polyvinyl chloride forming mixture consisting of 650 g ofpolyvinyl chloride, 350 g of dioctyl phthalate and 2% of a stabilizerbased on the polymer was mixed with 2.5% of the ultra-fine powder ofSynthetic Example 11, subjected to a roller mill at 150° to 160° C. for1 hour and extruded in a film. An opaque polyvinyl chloride film withgood whiteness degree was obtained.

In the above described procedure, when adding a suitable fluorescentwhitening agent, the high whiteness degree was further improved.

Example 8

(Surface Coating of Urethane Synthetic Resin Leather)

A liquid composition for a surface layer, shown in Table 6, was coatedonto a mold release paper to give a coverage of 130 g/m² by means of adoctor knife and dried at 90° to 110° C. for 2 minutes. Then, onto thesurface layer was coated a liquid composition for an adhesive layer,shown in Table 7, to give a coverage of 150 g/m² and further pastedbasic cloth (cotton carding cloth, thickness 1 mm) through apredetermined gap of laminate rolls, followed by drying by hot air at110° to 130° C. for 2 hours. The coated product was then aged underrolled state at 50° to 60° C. for 3 days, and after stripping themold-release paper, was subjected to surface finishing several times bygravure rolls using a liquid composition for surface finishing, shown inTable 8, obtaining a synthetic leather prepared by coating in beautifulwhite.

Various CRISVONS (commercial name) and various GLOSILAC (commercialname) used in this Example were ones prepared by Dai-Nippon Ink KagakuKogyo KK.

                  TABLE 6                                                         ______________________________________                                        Liquid Composition for Surface Layer                                          ______________________________________                                        CRISVON 7367 SL (urethane resin powder,                                                                100 g                                                solid content 35%, DMF/MEK 2:1)                                               Ultra-fine Powder of Synthetic Example 1                                                                5 g                                                 MEK (methyl ethyl ketone)                                                                              30 g                                                 DMF (dimethylformamide)  10 g                                                 total                    145 g                                                ______________________________________                                    

                  TABLE 7                                                         ______________________________________                                        Liquid Composition for Adhesive Layer                                         ______________________________________                                        CRISVON 4010 HV (thermosetting urethane                                                                   100 g                                             resin liquid)                                                                 CRISVON NX (isocyanate type cross-linking agent)                                                          8 g                                               CRISVON Accel HM (crosslinking accelerator)                                                               3 g                                               DMF                         5 g                                               Toluene                     5 g                                               total                       121 g                                             ______________________________________                                    

                  TABLE 8                                                         ______________________________________                                        Composition for Surface Finishing                                             ______________________________________                                        GLOSILAC CLEAR L-0465 (surface finishing agent)                                                            100 g                                            GLOSILAC CLEAR MAT L-0465 (surface finishing                                                               50 g                                             agent)                                                                        Thinner                      50 g                                             total                        200 g                                            ______________________________________                                    

Example 9

(Addition to Gloss Paint for Drying at Normal Temperature)

A white paint for drying at normal temperature, consisting of acomposition of the following Table 9, was prepared. This composition hada good stability and resistance to storage for a long time. A coatingfilm of this composition exhibited a high luster, excellent waterresisting property and alkali resisting property.

                  TABLE 9                                                         ______________________________________                                        White Paint Composition for Drying at Normal                                  Temperature                                                                   ______________________________________                                        Water                      52.5    g                                          Anionic Surfactant (Tamol 731 (25%), commercial                                                          9.0     g                                          name, made by R & H Co.)                                                      Nonionic Surfactant (Noigen EA 120, commercial                                                           2.2     g                                          name, made by Daiichi Kogyo Seiyaku KK)                                       Ultra-fine Powder of Synthetic Example 1                                                                 275.0   g                                          Ethylene Glycol            50.0    g                                          Defoaming Agent            2.0     g                                          28% Aqueous Ammonia        1.0     g                                          High Molecular Emulsion type Thickener (3%)                                                              34.8    g                                          Acryl-Styrene type Emulsion (VONCOAT EC-880                                                              853.8   g                                          (50%), commercial name, made by                                               Dai-Nippon Ink Kagaku Kogyo KK)                                               Silicone type Resin Film-forming Aid (Texanol                                                            60.7    g                                          SC-12, commercial name, made by Chisso KK)                                    total                      1341.0  g                                          ______________________________________                                    

Example 10

(For Baking Finish)

A paint for baking finish, comprising a composition of Table 10, wasprepared and sprayed and coated onto a soft steel plate of 0.8 mm inthickness by an air spray using xylene as a thinner to form a coatedfilm (coated film 30 to 35 μm, dr). The thus coated steel was allowed toset at room temperature for 15 minutes and then subjected to a heattreatment at 130° C. for 20 minutes, thus obtaining a coated film ofbeautiful white, excellent in luster, hardness and alkali resistance.

    ______________________________________                                        Paint Composition for Baking Finish                                           ______________________________________                                        Ultra-fine Powder of Synthetic Example 1                                                                70 g                                                Commercial Available Coconut Oil Alkyd                                                                 116 g                                                n-Butylated Melamine Resin                                                                              50 g                                                total                    236 g                                                ______________________________________                                    

The alkylenebismelamine derivative for a white pigment, represented byGeneral Formula (I) according to the present invention, is excellent incompatibility with the above described surfactants, various additives orother organic color pigment components because of being an organicmaterial. Accordingly, the pigment composition of the present inventionhas such an excellent dispersion stability and storage stability thatthe pigment components are hardly aggregated to cause seeding orseparating during storage. Furthermore, the organic white pigmentcompound of the present invention is also excellent in heat resistance,which is useful for a processing carried out at a high temperature, e.g.baking finish or dope dyeing of various polymers.

As described above, the alkylenebismelamine derivative for a organicwhite pigment according to the present invention has broad applications,for example, coating agents of papers, aqueous or oily paints forvarious coatings, printing inks, pigments for oil colors or crayons,pigments for printing or dope dyeing of polymers.

What is claimed is:
 1. An alkylenebismelamine derivative represented bythe following formula (I): ##STR14## wherein X is an alkylene groupcontaining 2 to 3 carbon atoms;R is cyclohexyl; R_(l) and R₂ are eachlower alkyl containing 1 to 4 carbon atoms, or R₁ and R₂ combine with anadjacent N atom to form a piperidino or morpholino group; and R₃ and R₄are each lower alkyl containing 1 to 4 carbon atoms, or R₃ and R₄combine with an adjacent N atom to form a piperidino or morpholinogroup.
 2. An alkylenebismelamine derivative according to claim 1,wherein R₁, R₂, and an adjacent N combine and R₃, R₄, and an adjacent Ncombine each to form piperidino group.
 3. An alkylenebismelaminederivative represented by the following formula (I) : ##STR15## whereinX is an alkylene group containing 2 to 3 carbon atoms;R is selected fromthe group consisting of hydrogen, lower alkyl containing 1 to 4 carbonatoms, and cyclohexyl; R₁, R₂ R₃, and R₄ are each butyl or R₁ and R₂combine with an adjacent N atom to form piperidino, and R₃ and R₄ areeach butyl or combine with an adjacent N atom to form piperidino.
 4. Analkylenebismelamine derivative selected from the group consisting ofN,N'-bis-(4,6-bis-morpholino-1,3,5-triazinyl-2)-ethylenediamine andN,N'-bis-(4,6-bis-piperidino-1,3,5-triazinyl-2)-ethylenediamine.